The basic configuration of this type of branch connector includes a pair of split housings capable of opening and closing with respect to each other so as to clamp a cable and a relay contact supported by the pair of split housings and configured to connect electrically to a cable guided by the pair of split housings when the pair of split housings are in a closed state.
Broadly speaking, relay contacts come in two types. The first type includes a pressure-contact groove for pressure contacting an existing cable and a pressure-fixing terminal for pressure fixing another cable, for example as in patent literature (PTL) 1. The second type includes a pair of pressure-contact grooves in parallel for pressure contacting an existing cable and another cable, for example as in PTL 2.
Regardless of which type of relay contact a branch connector includes, the cables are typically tightly clamped (with no gap in a radial direction) and held between the pair of split housings to prevent water from coming into contact with the relay contacts or the cables inside the branch connector.